More than a third of the US population lives in areas where air pollution levels frequently exceed EPA's health-based standards. As of the present time, there is a lack of clarity about the role and levels of specific components that are harmful to human health. Ongoing UAB research is designed to focus on the role of specific particulate matter (PM) components, aeroallergens and volatile organic compounds (VOCs) on cardiovascular and respiratory diseases and on daily mortality counts. The specific aims are to: (1) estimate correlation of air quality measurements from different sources (EPRI monitor and the state monitors); to collect and evaluate health outcome data; (2) to evaluate the association between PM2.5 and its components (sulfates, organic compounds, water-soluble transition metals, elemental carbon and acidity), ultrafine PMs (10 to 100 nm), and other pollutants on emergency department (ED) visits for cardiovascular and respiratory diseases ; and (3) between these pollutants and non non-accident all cause mortality and on mortality due to cardiovascular and respiratory diseases.